I used these resources when researching the annotations for this fairy tale. Most should be available through your local library, but I have included links to the titles on Amazon.com for further reading.

Altman, Anna E. and Gail de Vos. Tales,
Then and Now: More Folktales As Literary Fictions for Young Adults. Englewood,
CO: Libraries Unlimited, 2001.
Amazon.com: Buy it in paperback.